A multi-viewpoint video is a three-dimensional extension of the traditional movie sequence, in that multiple perspectives of the same scene exist at any instance in time. In other words, the multi-viewpoint video offers the capability of "looking around" objects in a scene. Thus, typical uses may include interactive applications, medical surgery technologies, remote sensing development, virtual reality games, etc.
With the development of digital video technology, a video data compression standard, namely the second Motion Picture Experts Group specification (MPEG-2), has been adopted by the International Standards Organization (ISO) and the International Telecommunications Union (IUT). MPEG-2 is a coding standard specified for one video sequence. MPEG-2 has also been recently shown to be applicable to two sequences of stereoscopic signals through the use of additional vectors. For purposes of this application, the relevant parts of sections 6 and 7 of the ISO document DIS 13818-2 will be hereinafter referred to as the "MPEG-2 standard."
However, extending the number of viewpoint videos beyond two views cannot be done practically by using the same methodology as the number of vectors would grow exponentially. Instead, a multi-viewpoint coder/decoder should compress the digital information so that information can be sent using as little bandwidth as possible.
In addition, a multi-viewpoint coder/decoder should be compatible with prior standards. In other words, while a TV may not properly show the different viewpoints in the multi-viewpoint video, the TV should be able to decode one viewpoint.
A multi-viewpoint coder/decoder should also be open-ended. In this manner, individual coding modules can be improved in accordance with any technological advances as well as the creativity and inventive spirits of software providers. An open-ended scheme would also allow a person to adjust the quality of the multi-viewpoint video according to system requirements and variables. Furthermore, such scheme would be easily expandable to provide as many video viewpoints as desired.
Finally, a multi-viewpoint coder/decoder should be hardware-based, instead of software-based. In this manner, fast and efficient coding/decoding can be achieved.